Campbell CS230, Field Maintenance And Instruction Manual

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CS230 Temperature Profiler
8
lifetime and user resettable minimum and maximum temperature values are
single 1 second readings. For more details, see TABLE 7-3 .
The CS230 complies with a subset of the SDI-12 1.3 instruction set.
Specifically, it supports these SDI-12 commands:
•
a! acknowledge active of individual sensor
•
aI! , send identification
• aR! ( aR0! to aR7! ), continuous measurements of the sensor. The R
command provides a faster means of obtaining the readings for
sensors that can provide continuous measurements. This instruction
usually takes less than 300 milliseconds to execute.
• aM! , initiate measurement (and the subsequent aD0! “get data”
command which is automatically sent by a Campbell Scientific
datalogger). This instruction usually takes about 700 milliseconds to
execute.
• aAb! , change address a to b
Where in all cases “a” is the address of the sensor and “!” is the command
terminator. These two characters are normally sent implicitly by Campbell
Scientific dataloggers.
The CS230 output is measured using a standard SDI-12 instruction to read the
data from an SDI-12 sensor. For CRBasic dataloggers, the SDI12Recorder()
instruction is used. For Campbell Scientific Edlog dataloggers, Instruction 105
is used. If using the sensor with other SDI-12 recorders, please refer to your
system’s documentation.
In any configuration of CS230 that includes more than one sensor,
the CS230 will not respond to the ?! SDI-12 command as each
individual sensor will respond at the same time thus disrupting all
outputs. Use the aI! command in a trial and error fashion if you
need to determine the individual addresses of temperature sensors.
NOTE